Fabrication and Characterisation of Polymer and Composite Scaffolds Based on Polyhydroxybutyrate and Polyhydroxybutyrate-Co-Hydroxyvalerate

Abstract

This paper reports the fabrication and characterization of three-dimensional, highly porous
polyhydroxybutyrate (PHB), polyhydroxybutyrate-co-valerate (PHBV) and composite scaffolds
made by the emulsion freezing / freezing-drying technique. Freeze-drying of the polymer/solvent/
water phase emulsions produced hard and tough scaffolds with interconnected pores. The effects of
the fabrication parameters such as polymer concentration in emulsions and emulsion stabilizer were
examined and optimized. The density of polymer scaffolds was found to increase with an increasing
polymer concentration. Structural analyses of selected samples using scanning electron microscopy
indicated that the scaffolds had pore sizes ranging from several microns to a few hundred microns.
The porosity of scaffolds of up to 85% was achieved and it increased with a decreasing polymer
concentration. It was found that mechanical properties of composite scaffolds increased with the
increasing amount of hydroxyapatite (HA) incorporated in the scaffolds.